Azo dyestuff derived from pyrazolone and process of making the same



Patented Apr. 1. 1924.

UNITED STATES AUGUST HEINRICH SCHOBEL, F BASEL,

' titans Parana @FFWE.

SWITZERLAND, ASQIGNOR T0 SOCIETY OF CHEMICAL INDUSTRY I N BASLE, 0F BASEL, SWITZERLAND.

AZO DYESTUFF DERIVED FRQM PYRAZOLONE AND PRGCESS 0F MAKING-THE N 0 Drawing.

the material printed with the new dyestufi'w I have found that a new and valuable amdyestufi derived from pyrazolone may he obtained by combining the diam-derivative of the Q-amino-l-phenoli-sulfo-6-carboxylic acid with the 1- (3carb0xy) -phenyl-5-pyrazolone-3-carboxylic acid.

The new dyestufi' corresponds with the formula: (|)H n o coon/\Nseai 2s 1 COOH- =N N n.

' and forms a reddish-brown powder dissolving in water with orange color, becoming yellow on addition of caustic soda. It dissolves in concentrated sulfuric acid to a yellow solution and printed on cotton by means of chromium niordants, it yields very bright and fast red orange tints.

E mample.

23.3 parts of 2-a1nino-1-phenol-4 sulfo-6- Application filed November 5, 1923. fierial Ho. 67 33%.

carboxylic acid are diazotized in the usual manner and introduced into an aqueous solution containing 29.6 parts of the disodium salt of the l-(3-carhoxy)-pheny1-5-pyrazo lone'3-carboxylic acid and an excess of sodium carbonate. The dyestufi thus obtailned is thrown out by means of common sa t.

What I claim is:

1. As a new product the herein described new azo-dyestufi' derived from pyrazolone which corresponds with the formula:

,forming a reddish-brown powder which dissolves in water with orange color, becoming yellow on addition of caustic soda, dissolving in concentrated sulfuric acid to a yellow solution, and ielding, printed on cotton by means of chromium mordants, very bright and fast red orange tints.

'2. Material printed with the azo-dyestutf of claim 1.

In witness whereof I have hereunto signed my name this 24th day of. October, 1923, in the presence of two subscribing witnesses.

AUGUST HEINRICH SCHOBEL.

Witnesses AMAND BRAUN, LUCIEN BICARD. 

